The drug promotes sensitivity to the hormone leptin, a naturally occurring appetite suppressant

A new weight-loss drug may help people shed weight and keep the pounds at bay, according to a study published in the journal Cell Metabolism.

The weight-loss drug, which has so far only been tested in mice, increases sensitivity to the hormone leptin, an appetite suppressant found naturally in the body. Researchers believe this discovery will aid in developments to combat obesity in humans.

According to George Kunos of the National Institute on Alcohol Abuse and Alcoholism, “By sensitizing the body to naturally occurring leptin, the new drug could not only promote weight loss, but also help maintain it. This finding bodes well for the development of a new class of compounds for the treatment of obesity and its metabolic consequences.”

Kunos has said that because the new weight-loss drug has only been tested in mice, it’s not clear whether the effects will translate to people. Human testing of the weight-loss drug will begin once the drug passes a safety test required by the National Institutes of Health, according to Kunos.

Leptin may supress appetite, but those who have taken leptin supplements alone have not witnessed a reduction in body weight for reasons not quite clear. Researchers believe this is due in large part to desentization of the hormone as it is found naturally within the human body.

Researchers believe cannabinoid receptors, the same receptors activated by chemicals in marijuana that promote feelings of hunger in marijuana smokers, contribute to the desensitization process. Blocking cannabinoid receptors has been shown to cause weight loss; however, a previously developed weight-loss drug, rimonabant, that blocked cannabinoid receptors caused serious psychiatric side effects, including anxiety, depression and suicidal thoughts. Rimonabant was taken off the market after initially being sold in Europe beginning in 2006.

The new weight-loss drug, called JD5037, was designed to not enter the brain so as to reduce psychatric side effects. According to Kunos, the drug blocks cannabinoid receptors in other parts of the body, including the liver and musle tissue.

Obese mice given the weight-loss drug for approximately a month lost 28 percent of their body weight and, according to Kunos, reached the weight of an average-size mouse. The mice accomplished this weight-loss despite continuing to eat the same high-fat diet that initially led to their obesity. There were no psychiatric side effects reported in the mice tested with the drug.

Obesity rates among American adults have risen to 35 percent, which has brought about calls for the FDA to approve new weight-loss treatments; however, a littany of prescription diet pills have been seen as dangerous with side effects including heart problems.

“Obesity is a growing health problem, and there is strong need for new types of medications to treat obesity and its serious metabolic complications, including diabetes and fatty liver disease,” Kunos concluded.